Polymers of linear formals



linear formals.

Patented Apr. 6, 1948 POLYMERS OF LINEAR FORMALS William F, Gresham,Wilmington, Del., assignor to E. Ldn Pont de Nemours a Company, Wil-,mington, Del., a corporation oi Delaware I 7 No Drawing.

Original application May 6, 1941,

- Serial No. 392,127. Divided and this applicatlon January 8, 1945,Serial No. 571,956

10 Claims. 1

This invention relates to a process for the preparation of oxygenatedorganic polymers and more particularly to polymers obtained from linearformals. This case is a division of U. 8. Patent No. 2,382,938, patentedAugust 14, 1945.

An object of the present invention is to provide new polymeric compoundsand processes for their preparation. Another object is to provide newpolymeric compositions'from polymerizable Yet another object is toprovide a process for the polymerization of linear formals. Stillanother object is to provide mixtures or interpolymers of linear iormalswith homologous polymerizable compounds, or with cyclic and alicyclicalkylene oxides and the like.

, Other objects and advantages of the invention will hereinafter appear.

It has been found that linear formals containing two or more functionalgroups, such groups being defined for the purpose-oi the specificationas hydroxyl groups (OH) and formal groups (OCH2O-), can be reacted togive products having a wide range of physical and chemical properties bycontacting them with a suitable catalyst under properly controlled con-25 ditions. These products will be defined as polymers, which term willinclude the chemical combination of at least two polyiunctional lineariormals as well as the intermediate products resulting from thepolymerization which contain 30 at least two glycol residues, e. g., theresidues -CH2CHzO and/or CH2CH2OH.

The linear formals containing two or more functional groups which may bepolymerized, in accord with the invention include, for example: methylhydroxyethyl formal,

methyl-, ethyl-, propyl-, butyl-, and methoxyethyl-hydroxypropylIormals, which may be 11- lustrated by the formula ROCI-IzOCaHsOH, in awhich the R group is respectively methyl, ethyl,

propyl, butyl, methoxyethyl, etc., and the higher alkyl hydroxyalkylformals such as are disclosed 2 in the copending application of Sussmanet al., S. N. 288,587, filed 'August 5, 1939 dKp-hydroxyethyl) formal,(HOCHzCI-I2O)2CH2, dip-(hydroxyethoxy) methoxy ethane,

@ rnocrncmocnzoncim (HOCHzCHzOCHzOCHzCI-IzO) zCHz higher homologues wHOCH2CH2(OCH2OCH2CH2):OH

where a: is greater than 3; 1,2-diiisobutoxy methoxy) ethane,

C4H9OCH2OCH2CH2OCH2OC4H9 and compounds of the general typeROCHzOCHzCHaOCHzOR in which R is a lower alkyl group such as aredescribed in U. S. 2,350,350 of W. F. Gresham,

patented June 6, 1944, and which are prepared by the polymerization ofthe reaction product from vicinal glycols and aldehydes in the presenceof an acidic catalyst, which catalyst is destroyed before separating theproduct. Polypolymerizable, e. g.,

Polymers may likewise be obtained from such compounds asp-(methoxymethoxy) ethyl(meth- 85 oxymethoxy) acetatecmocrnocmcoocnzcrnocnzocns and similar p-(alkoxymethoxyethyl) esters ofalkoxy methoxy .carboxylic acids and from m- 40(p-methoxymethoxy)ethanol, esters of the dibasic acids,

cmocmocmcmooc wmncoocmcmocmocm in which a: is greater than one, and thedi(pmethoxymethoxy) ethyl esters of 1,1-di-(carbomethoxymethoxy)methane, these esters being obtainable by ester interchange of1,1-di-(carbo methoxymethoxy) methane,

disclosed in the copending application of Loder et al., U. $2,364,455,patented December 6, 1944,

which describes the preparation of the acetals Bl of hydroxy aliphaticacids and their esters by formal esters of polybasic acids are likewisethe (methoxymethoxy)- ethanol esters of oxalic, malonic, succinic,glutaric, adipic, pimelic, and the higher aliphatic dibasic acids aswell as phthalic acid and the interaction of'hydroxy aliphatic acids ortheir esters with aldehydes in the presence of an acid catalyst, and the(alkoxymethoxy) ethanols ROCHzOCHzCHzOH disclosed in the copendingapplication of Sussman et al., S. N. 288,587, which are prepared by thereaction of vicinal glycols with acetals in the presence of an acidiccatalyst, the ester interchange reaction being carried out in thepresence of an alkaline catalyst, such as sodium methoxide. Polymers ofthe latter types will have terminal reactive groups. Low molecularweight polymers of the linear formals of the invention can also beconverted to higher molecular weight polymers by the process of theinvention.

The polymerization is efiected at temperatures ranging between -80 and+300 C. and preferably between and 150 C. Atmospheric, suborsuperatmospheric pressures may be used, and if the last, pressures mayrange between 1 and 1000 atmospheres or higher. Normally excellentresults are obtained at or about atmospheric pressure. If desired, thetemperature of the reaction, especially when polymerization is carriedout at the boiling point of the reaction mixture, may be controlled byvarying the pressure on the boiling reactants.

It has been found advantageous to efiect the polymerization in thepresence of an acidic type catalyst such, for example, as sulfuric acid,phosphoric acid, hydrochloric acid, hydrofluoric acid (alone or withBFa), boron fluoride (including its complexes with water, acids, esters,alcohols, and the like), paratoluene sulfonic acid, camphor sulfonicacid, and other acid catalysts of this general nature. Frledel-Craftstype catalysts other than BF: may be used, such as AlCls, A-lBra, FeCla,and so forth, as well as inorganic acids generally and their acid saltssuch as sodium acid sulfate, sodium acid phosphate, and so forth.

The catalyst may be supported or not on inert supports such as charcoal,silica gel (which alone is a catalyst for the reaction), kieselg uhr,and so forth. Concentrations of BFs, H2804, and similarly strong acidcatalysts may be extremely low, less than 0.1%, and amounts down to aslow as 0.001% of these strong acid catalysts have been found suflicientto give polymers although high concentrations of the catalyst even equalto or greater than the weight of the linear formal are likewisesatisfactory.

The reaction is preferably continued approximately to equilibrium inorder to efiect the polymerization, or, if desired, reaction productsare separated to force the reaction in one direction .and until themolecular weight distribution wanted in the final product is attained.The reaction is generally continued for from 0.5 to hours at temperatureranges between 25 and. 150 C. and from 1 to 10 days at temperaturesbelow 0 C., although shorter or longer reaction times may be employed,if desired; and the reaction may then be stopped by destroying thecatalyst. This may be done by removing it (in the case ofsi-lica gel,kieselguhr, and the like) or by treating the reaction mixture with aninorganic base, such asammonia, alkali metal, and alkaline earth metalhydroxides, carbonates, alkoxides, and soforth or an organic base, suchas pyridine, dimethylam'ine, and the like. These bases are added insuflicient amounts to .neutralize the catalyst when acid catalysts areused, and the unconverted reactants may be removed, continuously if,desired, by distillation under reduced pressures. As soon as thecatalyst has been neutralized, the reaction ceases. catalyst may befiltered off and the polymerized product which remains treated for therecovery of the polymers.

The linear formals may be polymerized in various ways. Thepolymerization may be carried out by treating the monomer and catalystin the presence or absence of a solvent for the monomer and polymer andfor this type of polymerization, such solvents as 1,4-dioxane, benzene,and toluene may be used. I

The polymerizable linear formals above referred to can be converted toproducts having a wide range of physical and chemical properties,

by simultaneous polymerization in contact with such as ethylene oxide,1,2- and 1,3-propylene oxides, tetramethylene oxide, isobutylene oxide,and their isomers and metamers. Interpolymers may likewise be made bypolymerizing one linear formal of the class specified with anotherlinear formal of the class. For example, interpolymers can be made bythe simultaneous polymerization, in contact, of (methoxymethoxy)ethanolwith di(beta hydroxyethyDformal, any amount of the (methoxymethoxy)ethanol from 1 to 1000 per part of the di(beta hydroxyethyDformal may beused.

The polymerization of polyfunctional linear formals does not ordinarilyproduce a single polymeric product, but generally gives two or more suchproducts, the distribution of polymers present being determined interalia by the temperature of the reaction and the type and concentrationof catalyst employed. It may be desired to obtain from these products agiven polymer and this can be effected by carrying out thepolymerization by a process wherein a portion of the desired product isremoved from the reaction zone and the undesired products returned tothat zone together with the linear formal being polymerized.

Examples will now be given illustrating embodiments of the invention,but it will be understood that it will not be limited by the detailsthereof. Parts are by weight unless otherwise indicated.

Example 1.A reaction mixture consisting of 1060 parts of(methoxymethoxy) ethanol and 3 parts of sulfuric acid was heated on awater bath at 4050 C. and 28 mm. until 386 parts of lower boilingproducts were collected in a dry-ice cooled trap which was placedbetween the reaction vessel and a vacuum pump. The sulfuric acid wasneutralized with a 28% solution of sodium methoxide. Materials boilingup to approximately 75 C./3 mm. were removed. This gave 559 parts of awater-white viscous liquid polymer which was soluble in water, benzeneand methanolhydroxyl No. 312; density at 25 C., 1.160; refractive indexat 25 C., 1.5000; estimated molecular weight in boiling benzene, 320.

Example 2.-A reaction mixture, prepared by careful addition of 4 partsof sulfuric acid to 573 g.- of (methoxym'ethoxy)ethanol, was processedunder conditions set forth in Example 1 and until 152 parts of lowerboiling materials collected in the dry-ice trap. Subsequent toneutralization of the catalyst with sodium methoxide The neutralizeddissolved in methanol, distillation under 3 mm. pressure, carried outuntil the head temperature reached 115 0., gave 216 parts of a.colorless viscous liquid polymer-hydroxyl N0. 826; density at 25 0.,1.080; refractive index at 25 6., 1.4480. The polymer was soluble inwater, benzene and methanol.

Example 3.--A mixture consisting of 416 parts 7 of p- (methoxymethoxy)ethyHmethoxymethoxy) acetate, CHaOCHaOCHaCOOCI-IzCHzOCHrOCHa, and 1 partof sulfuric acid was heated on a water bath under 40 mm. pressure until115 parts of 'methylal was removed. The catalyst was neuhydrous ammoniato destroy the catalyst, dissolved in benzene and the benzene filteredto remove inorganic precipitates. Removal of benzene under reducedpressure, finally to 1 mm.

and 100 0., gave 21.5 parts of a viscous liquid polymer which wassoluble in water.

Example 5.-A mixture of 62.3 parts of di- (methoxymethoxy ethyl) adipateand 0.09 part of concentrated sulfuric acid was heated under reducedpressure at a pot temperature of 170 C. until 14 parts of methylal wasremoved. After the addition of 0.1 part of NaOH in 2 parts of water, thereaction mixture was topped to remove water and then filtered. Thepolymer, a pale yellow, viscous liquid, was soluble in benzene andinsoluble in alcohol and water. Molecular weight in boiling benzene 728.

The compounds prepared in accord with the invention may be employed fora large number of uses. The lower molecular weight polymers and/orsolutions of the higher molecular weight polymers in water or othersuitable solvent may be employed in the uses designated below whichrequire solubilized agents; e. g., as solvents, extractors, fungicidaiuses, and so forth. The higher molecular weight polymers may beused asproduced or in solution in many of the designated uses, such, forexample, as those described under cosmetics, elastomers, leather andrelated materials.

In the textile industry, solutions of the polymers may be used as sizersfor nylon, rayon, wool, silk, and cotton; as a size lubricant; or as atextile softener to improve hand, either as such or after treatment, e.g., after shrinkproofing. The polymers may also .be employed as;plasticizers for artiflcial yarns; spinning assistants; mercerizingassistants; and modifying assistants for dye receptivity. They may beused for improving dye fastness; increasing cleaning, wetting,dispersing, spreading, emulsifying, levelling and dyeing capacities;falling, aftertreating, washing,and carbonizing: v cross-linking(especially hydroxy-containingl polymers; and may be used to preventmildew, rot and fungi infestation; improve creaseproof, crushproof andcrinkleproof characteristics of textiles; and to give a permanenttextile finish.

In the paint, varnish, polish and finishing industries, the polymers maybe used in the prepetc; as dressings for belts as non-slip, antisqueakand as a general preservative. They are useful as, ingredients inadhesive; dispersing,

spreading, binding, and wetting agent :in paint, pigments, and lakes; asan agent to prevent livering in paints; as a substitute foralkydvarnishes and resins; as a termite repellent in lacquers and paint; asan ingredient of slow drying lacquers: as a binder for ceramic glazes-tobe subsequently fired; and as wax and resin plasticizers generally.

In the preparation and use of ink the polymers described may be employedin the print roll composition; as an addition agent to the ink or to theroll to improve offsetting qualities, both in the offset process and to.prevent offset or smear between sheets; as an emulsifying, spreading,binding, dispersing, agent, tack and viscosity improver, adhesionassistant, and livering preventive in printing inks; as a suspendingmedium for printing pastes; as an ingredient in duplicators, either inthe ink or in the pad; and as a, gloss improver.

The polymers are likewise useful in the paper industry as a paper sizefor waxing to make paper and cardboard oilproof and airproof; forimproving wet strength of paper, as a substitute for natural waxes incarbon paper, as a paper plasticizer, coating for paper condensers andinsulators, and for transparentizing paper.

In the rubber fleld'the polymeric products may be used as preservatives,rubber plasticizers, plasticizers for artificial rubber-like materials,protective coating for rubber, as an ingredient for incorporation witheither rubber or artificial rubher to make them resistant to oil andgasoline,

to improve low temperature flexibility, as an antioxidant, ozoneresistant, and for making artificial rubber-like materials by reactingthe polymers with glue.

Leather and related materials may be improved by these polymers as theiruse renders such materials fat-resistant. Furthermore, they may be usedin fur mordanting, as a tanning agent, as an ingredient to make leathersoft and pliable, as a preservative for footwear, ornaments, leatherbelting, etc., and as a ,Fabrikoid" softener and coating agent.

These polymeric compounds have many important uses in the cosmeticindustry as, for example, an emulsifying agent and as an ingredient increams, lotions, lathers, hair dressings, etc.; are adaptable for use inthe preparation of antiseptic soaps and as a binder for hand, abrasive,

and toilet soaps; as an invisible glove component for ointments andsalves.

vegetables, eggs, foods, etc., to be applied as a a I melt or solutionto the comestibles against air and moisture; for the preparation oftranslucent screens; as an interpolymer with ethylene, oxide,

- ethylene, vinyl compounds, or rubber-like polymer forming materials:and as a plastic emulsion ingredient.

The polymers may be likewise employed as plasticizers for cellulose andcellulose derivatives; for shrlnkprooflng acetate silk; as a sealingagent for oil and gas wells; drilling mud ingredient to controlthixotropy, settling, etc.; grinding aid in clinker cement, flotationagent in ore treating,

improving root growth, as an ingredient in insect and fungicidal sprayseither as adhesive or active agent; as a water soluble wire and metallubricant; as a bonding agent for finely dividedmaterials; for sealingwounds in trees; as a water soluble ingredient for addition to artistscrayons;

as a surface tension depressant for use with other surface activematerials; as a plasticizer for glue, casein, proteins, gelatin, cork,etc. They may be employed as substitutes for glycerine foots inelectroplating baths; as a cutting aid in metal turning; and as a metalcleaner, The polymeric products likewise may be incorporated withgreases to improve lubrication, consistency, and the viscositycoemcient; as a gas absorbent; poison gas collector; dust collector inair conditioning; emulsifying agent in emulsion polymerization; as anaddition to cellulose films to render them non-curling; and as anaddition to cellulose nitrate and cellulose acetate to makenoncorrosive; as a binder for abrasive wheels which completelyvolatilizes on firing; and as an ingredientin self-sealingtubes andtires.

I claim:

1. A process of making polymerization products from an alkylhydroxyalkyl formal consisting of introducing an alkyl, hydroxyalkylformal into a reaction zone and subjecting it therein to polymerizationin the presence of an inorganic acid catalyst and thereafterneutralizing the catalyst to stabilize the polymer.

2. A process of making polymerization prod ucts from (methoxymethoxy)ethanol consisting of subjecting (methoxymethox y) ethanol topolymerization in the presence of a strong inorganic acid catalyst at atemperature between 0 and 150 C. and thereafter neutralizing thecatalyst to stabilize the polymer.

ucts from (meth'oxymethoxy) ethanol consisting ..oi. subjecting(methoxymethoxy) ethanol to poly merization in the presence of sulfuricacid at a temperature between 0 and C. and thereafter neutralizing thecatalyst to stabilize the polymer.

6. A process of polymerizing (methoxymethoxy) ethanol consisting ofsubjecting (methoxymethoxy) ethanol to a temperature between 40 and 50C. in the presence of 0.3% sulfuric acid as the catalyst under reducedpressure until 38% or the lower. boiling products are distilled over,and subsequently neutralizing the catalyst with a 28% solution of sodiummethoxide.

7. The polymeric product obtainedin accord with the process of claim 1.

8. The polymeric product obtained in accord with the process of claim 3.

9. The polymeric product obtained in accord with the process of claim 4.

10. The polymeric product obtained in accord with the process of claim6.

WILLIAM F. GRESHAM.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name 1 Date 2,129,694 Izard Sept. 13, 19382,321,542 Brooks June 8, 1943 2,321,593 Gresham -1 June 15, 1943

